Question

Can all the Arabic letters have med laaz harfi?

Answer

Only the letters have the both the condition of being a medd laazim harf (read as if it is three letters, the middle letter being either an alif or a lengthened ya’), and beginning some of the surahs of the Qur’an.  Other letters may be read as three letters, the middle letter being an alif or a lengthened ya’, but Allah, the Exalted, did not start any of the surahs in the Glorious Qur’an with these other letters.

A note about the letter .  This letter when pictured as a single identity is written out as:

The second letter is a ya’, but the vowel on the letter preceeding it is a fat-hah.                
The is one of the separated letters in the beginning of surah Maryam and surah Ash-shooraa. 

 

Because the middle letter is a leen letter (ya’ saakinah preceded by a fat-hah)  and not a medd letter, it can be lengthened 4 or 6 counts, by the way of recitation of Hafs ‘an Aasim by the way of Shatibiyyah.  This is not medd al-leen, but a follower of it.